[PATCH], V7, #5 of 7, Add more effective targets for the 'future' system to target-supports.

[Michael Meissner <meissner at linux dot ibm dot com>]

This patch adds more effective targets to the target-supports.exp in the
testsuite.  I tried to break it down to whether prefixed instructions are
allowed, whether the target is generating 64-bit code with prefixed
instructions, and if -mpcrel support is available.  I also enabled 'future'
testing on the actual hardware (or simulator).

The tests in V8 will use some of these capabilities.

I have run the test suite on a little endian power8 system with no degradation.
Can I check this into the FSF trunk?

2019-11-14   Michael Meissner  <meissner@linux.ibm.com>

	* lib/target-supports.exp
	(check_effective_target_powerpc_future_ok): Do not require 64-bit
	or Linux support before doing the test.  Use a 32-bit constant in
	PLI.
	(check_effective_target_powerpc_prefixed_addr_ok): New effective
	target test to see if prefixed memory instructions are supported.
	(check_effective_target_powerpc_pcrel_ok): New effective target
	test to test whether PC-relative addressing is supported.
	(is-effective-target): Add test for the PowerPC 'future' hardware
	support.

Index: gcc/testsuite/lib/target-supports.exp
===================================================================
--- gcc/testsuite/lib/target-supports.exp	(revision 278173)
+++ gcc/testsuite/lib/target-supports.exp	(working copy)
@@ -5345,16 +5345,14 @@ proc check_effective_target_powerpc_p9mo
     }
 }
 
-# Return 1 if this is a PowerPC target supporting -mfuture.
-# Limit this to 64-bit linux systems for now until other
-# targets support FUTURE.
+# Return 1 if this is a PowerPC target supporting -mcpu=future.
 
 proc check_effective_target_powerpc_future_ok { } {
-    if { ([istarget powerpc64*-*-linux*]) } {
+    if { ([istarget powerpc*-*-*]) } {
 	return [check_no_compiler_messages powerpc_future_ok object {
 	    int main (void) {
 		long e;
-		asm ("pli %0,%1" : "=r" (e) : "n" (0x12345));
+		asm ("pli %0,%1" : "=r" (e) : "n" (0x1234));
 		return e;
 	    }
 	} "-mfuture"]
@@ -5363,6 +5361,46 @@ proc check_effective_target_powerpc_futu
     }
 }
 
+# Return 1 if this is a PowerPC target supporting -mcpu=future.  The compiler
+# must support large numeric prefixed addresses by default when -mfuture is
+# used.  We test loading up a large constant to verify that the full 34-bit
+# offset for prefixed instructions is supported and we check for a prefixed
+# load as well.
+
+proc check_effective_target_powerpc_prefixed_addr_ok { } {
+    if { ([istarget powerpc*-*-*]) } {
+	return [check_no_compiler_messages powerpc_prefixed_addr_ok object {
+	    int main (void) {
+		extern long l[];
+		long e, e2;
+		asm ("pli %0,%1" : "=r" (e) : "n" (0x12345678));
+		asm ("pld %0,0x12345678(%1)" : "=r" (e2) : "r" (& l[0]));
+		return e - e2;
+	    }
+	} "-mfuture"]
+    } else {
+	return 0
+    }
+}
+
+# Return 1 if this is a PowerPC target supporting -mfuture.  The compiler must
+# support PC-relative addressing when -mcpu=future is used to pass this test.
+
+proc check_effective_target_powerpc_pcrel_ok { } {
+    if { ([istarget powerpc*-*-*]) } {
+	return [check_no_compiler_messages powerpc_pcrel_ok object {
+	      int main (void) {
+		  static int s __attribute__((__used__));
+		  int e;
+		  asm ("plwa %0,s@pcrel(0),1" : "=r" (e));
+		  return e;
+	      }
+	  } "-mfuture"]
+      } else {
+	  return 0
+      }
+}
+
 # Return 1 if this is a PowerPC target supporting -mfloat128 via either
 # software emulation on power7/power8 systems or hardware support on power9.
 
@@ -7261,6 +7299,7 @@ proc is-effective-target { arg } {
 	  "named_sections" { set selected [check_named_sections_available] }
 	  "gc_sections"    { set selected [check_gc_sections_available] }
 	  "cxa_atexit"     { set selected [check_cxa_atexit_available] }
+	  "powerpc_future_hw" { set selected [check_powerpc_future_hw_available] }
 	  default          { error "unknown effective target keyword `$arg'" }
 	}
     }

-- 
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meissner@linux.ibm.com, phone: +1 (978) 899-4797